Everton have been dealt a blow after Steven Pienaar suffered a hamstring injury that will rule him out for up to four weeks.

The South African forward sat out the 1-0 win over Chelsea after he sustained the problem during training at the club's Finch Farm base on Friday.

Roberto Martinez, whose side are unbeaten after four games, had hoped Pienaar would be up and running again quickly but the problem is more troublesome than it first appeared.

Blow: Everton's Steven Pienaar (centre) will miss several key games after suffering a hamstring injury

Pienaar is one of Everton's most
influential performers but will miss games against West Ham, Newcastle
and Fulham in the Capital One Cup. If his recovery goes smoothly, he
could be in line to return for the trip to Manchester City on October 5.

Though Martinez is also without Darron Gibson and Antolin Alcaraz, who are working their way back after injuries, he does have options in his squad and he is adamant those options will provide him with goals.

Everton have only managed three goals in their opening four Premier League fixtures and Martinez has arrived at Goodison Park following a season at Wigan when they only managed to outscore seven of the 20 teams in the division.

Goals will come: Roberto Martinez is confident Everton will soon start hitting the net on a regular basis

Marouane Fellaini, who was a huge goal threat, has also left but Martinez is adamant that it is only a matter of time before Everton's forward play gets the rewards it deserves.

'The goalscoring ability of a team is one of the biggest points in being able to be successful,' said Martinez. 'I don't think you when you rely on one player you are going to be successful in the long term. Clearly in the first few games we have not scored enough goals.

'But we have been having opportunities and I like the way we have been controlling games. Now the work is to have enough goals in the side. I don't think we can rely on one person, to rely on one player to score you 25 goals.

Main man: Steven Naismith scored the winner as Everton stunned Jose Mourinh's Chelsea at the weekend

'Those players don't exist, or if they exist they will move on after 10 months because that is the market forces. That is where the work is. We need to be able to score goals from all over the park and share the responsibility. That is where the work is.'

Martinez will, at least, by able to call on new loan signing Romelu Lukaku this weekend. The Belgium international was ineligible for the Chelsea game under the rules of his loan but Martinez hopes he can have a similar impact on Merseyside as the one he had for West Brom.

'Sometimes as a club you need to make a decision if the right role at your club is the right one for an individual,' he said. 'And Romelu now needs to play minutes. Scoring 17 goals in the league last season needs to be taken to the next level and carry on playing minutes.